- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Compiler version: icc 17.0.1 20161013
OS version: macOS Sierra 10.12.1
The code below generates wrong output.
#include <stdio.h>
int main(void)
{
#pragma omp parallel for
for (int i = 1; i < 2; i++) {
#pragma omp parallel for
for (int j = 0; j < 1; j++) {
printf("%d\n", i);
}
}
}
Expected result: 1
Actual result: 0
Link Copied
9 Replies
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
The loop itself is quite odd. You are creating a team of parallel threads to execute only 1 iteration, and later creating for each of the original threads another team, i.e. a team of teams, just to execute one more iteration. This code is useless.
By the way, I was not able to reproduce the problem with 0 output. How did you compile this test?
In addition, you may use a collapse clause to parallelize nested loops. However, in this example it doesn't make sense to use OpenMP.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
I compiled this with `icc -qopenmp foo.c`.
I know this code is not useful, but this is at least an legal OpenMP code. I inteded to make the code as minimal as possible, while it can reproduce the problem. The problem is that the compiler does not seems to make the variable i "shared" for inner parallel for region. The variable i should be implicitly shared according to the OpenMP specification.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Igor,
FYI Reproducers are typically pointless. The structure of the reproducer in #1 is perfectly valid (regardless of being useless).
Daisuke,
Can you debug the reproducer by placing a break at the printf. Try not to change the compiler switches. Then at the break point, use Disassembly, list the entire code of main, then use the {...}/code button to paste the text in to this forum code window (use plain text format).
If you do change options, assure that running without debugging reproduces your error.
Jim Dempsey
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
I compiled the code with `icc -qopenmp -g foo.c`. I confirmed the problem is still reproduced with -g option (and without debugging).
Here is the result of disassemble, using LLDB:
a.out`main:
0x100000978 <+0>: pushq %rbp
0x100000979 <+1>: movq %rsp, %rbp
0x10000097c <+4>: subq $0xc0, %rsp
0x100000983 <+11>: movq %r15, -0x8(%rbp)
0x100000987 <+15>: movq %r14, -0x10(%rbp)
0x10000098b <+19>: movq %r13, -0x18(%rbp)
0x10000098f <+23>: movq %r12, -0x20(%rbp)
0x100000993 <+27>: movq %rbx, -0x28(%rbp)
0x100000997 <+31>: leaq 0x6d6(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.1
0x10000099e <+38>: movl $0x0, %edx
0x1000009a3 <+43>: movq %rax, %rdi
0x1000009a6 <+46>: movq %rdx, %rsi
0x1000009a9 <+49>: movl $0x0, %eax
0x1000009ae <+54>: callq 0x100000ea4 ; symbol stub for: __kmpc_begin
0x1000009b3 <+59>: leaq 0x6e6(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.12
0x1000009ba <+66>: movq %rax, %rdi
0x1000009bd <+69>: callq 0x100000ec8 ; symbol stub for: __kmpc_global_thread_num
0x1000009c2 <+74>: movl %eax, -0x88(%rbp)
0x1000009c8 <+80>: leaq 0x761(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x1000009cf <+87>: movq %rax, %rdi
0x1000009d2 <+90>: movl $0x0, %eax
0x1000009d7 <+95>: callq 0x100000ece ; symbol stub for: __kmpc_ok_to_fork
0x1000009dc <+100>: movl %eax, -0x80(%rbp)
0x1000009df <+103>: movl -0x80(%rbp), %eax
0x1000009e2 <+106>: testl %eax, %eax
0x1000009e4 <+108>: jne 0x100000a39 ; <+193> at foo.c:5
0x1000009e6 <+110>: leaq 0x743(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x1000009ed <+117>: movl -0x88(%rbp), %edx
0x1000009f3 <+123>: movq %rax, %rdi
0x1000009f6 <+126>: movl %edx, %esi
0x1000009f8 <+128>: movl $0x0, %eax
0x1000009fd <+133>: callq 0x100000ed4 ; symbol stub for: __kmpc_serialized_parallel
0x100000a02 <+138>: leaq -0x88(%rbp), %rax
0x100000a09 <+145>: leaq 0x738(%rip), %rdx ; __kmpv_zero_main_0
0x100000a10 <+152>: movq %rax, %rdi
0x100000a13 <+155>: movq %rdx, %rsi
0x100000a16 <+158>: callq 0x100000b9e ; <+550> at foo.c:5
0x100000a1b <+163>: leaq 0x70e(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x100000a22 <+170>: movl -0x88(%rbp), %edx
0x100000a28 <+176>: movq %rax, %rdi
0x100000a2b <+179>: movl %edx, %esi
0x100000a2d <+181>: movl $0x0, %eax
0x100000a32 <+186>: callq 0x100000eb0 ; symbol stub for: __kmpc_end_serialized_parallel
0x100000a37 <+191>: jmp 0x100000a5f ; <+231> at foo.c:12
0x100000a39 <+193>: leaq 0x6f0(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x100000a40 <+200>: movl $0x0, %edx
0x100000a45 <+205>: leaq 0x152(%rip), %rcx ; <+550> at foo.c:5
0x100000a4c <+212>: movq %rax, %rdi
0x100000a4f <+215>: movq %rdx, %rsi
0x100000a52 <+218>: movq %rcx, %rdx
0x100000a55 <+221>: movl $0x0, %eax
0x100000a5a <+226>: callq 0x100000ec2 ; symbol stub for: __kmpc_fork_call
0x100000a5f <+231>: leaq 0x66a(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.20
0x100000a66 <+238>: movq %rax, %rdi
0x100000a69 <+241>: movl $0x0, %eax
0x100000a6e <+246>: callq 0x100000eaa ; symbol stub for: __kmpc_end
0x100000a73 <+251>: movl $0x0, %eax
0x100000a78 <+256>: movq -0x28(%rbp), %rbx
0x100000a7c <+260>: movq -0x20(%rbp), %r12
0x100000a80 <+264>: movq -0x18(%rbp), %r13
0x100000a84 <+268>: movq -0x10(%rbp), %r14
0x100000a88 <+272>: movq -0x8(%rbp), %r15
0x100000a8c <+276>: leave
0x100000a8d <+277>: retq
0x100000a8e <+278>: movl $0x1, -0x9c(%rbp)
0x100000a98 <+288>: movl -0xb4(%rbp), %eax
0x100000a9e <+294>: movl $0x1, %edx
0x100000aa3 <+299>: subl %edx, %eax
0x100000aa5 <+301>: movl %eax, -0x98(%rbp)
0x100000aab <+307>: movl -0xb4(%rbp), %eax
0x100000ab1 <+313>: movl $0x1, %edx
0x100000ab6 <+318>: subl %edx, %eax
0x100000ab8 <+320>: movl %eax, -0x94(%rbp)
0x100000abe <+326>: movl $0x0, -0x90(%rbp)
0x100000ac8 <+336>: movl $0x1, -0x8c(%rbp)
0x100000ad2 <+346>: addq $-0x20, %rsp
0x100000ad6 <+350>: leaq 0x653(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x100000add <+357>: movl $0x22, %edx
0x100000ae2 <+362>: leaq -0x90(%rbp), %rcx
0x100000ae9 <+369>: leaq -0x9c(%rbp), %rbx
0x100000af0 <+376>: leaq -0x98(%rbp), %rsi
0x100000af7 <+383>: leaq -0x8c(%rbp), %rdi
0x100000afe <+390>: movq %rdi, (%rsp)
0x100000b02 <+394>: movl $0x1, 0x8(%rsp)
0x100000b0a <+402>: movl $0x1, 0x10(%rsp)
0x100000b12 <+410>: movq %rax, %rdi
0x100000b15 <+413>: movl -0x74(%rbp), %eax
0x100000b18 <+416>: movq %rsi, -0x38(%rbp)
0x100000b1c <+420>: movl %eax, %esi
0x100000b1e <+422>: movq %rbx, %r8
0x100000b21 <+425>: movq -0x38(%rbp), %rax
0x100000b25 <+429>: movq %rax, %r9
0x100000b28 <+432>: callq 0x100000ebc ; symbol stub for: __kmpc_for_static_init_4
0x100000b2d <+437>: addq $0x20, %rsp
0x100000b31 <+441>: movl -0x9c(%rbp), %eax
0x100000b37 <+447>: movl %eax, -0x7c(%rbp)
0x100000b3a <+450>: movl -0x98(%rbp), %edx
0x100000b40 <+456>: movl %edx, -0x78(%rbp)
0x100000b43 <+459>: movl %edx, -0x78(%rbp)
0x100000b46 <+462>: movl -0x94(%rbp), %edx
0x100000b4c <+468>: cmpl %edx, %eax
0x100000b4e <+470>: jg 0x100000b6f ; <+503> at foo.c:5
0x100000b50 <+472>: movl -0x94(%rbp), %eax
0x100000b56 <+478>: movl -0x78(%rbp), %edx
0x100000b59 <+481>: cmpl %eax, %edx
0x100000b5b <+483>: jle 0x100000bf8 ; <+640> at foo.c:5
0x100000b61 <+489>: movl -0x94(%rbp), %eax
0x100000b67 <+495>: movl %eax, -0x78(%rbp)
0x100000b6a <+498>: jmp 0x100000bf8 ; <+640> at foo.c:5
0x100000b6f <+503>: leaq 0x5ba(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.49
0x100000b76 <+510>: movq %rax, %rdi
0x100000b79 <+513>: movl -0x74(%rbp), %eax
0x100000b7c <+516>: movl %eax, %esi
0x100000b7e <+518>: callq 0x100000eb6 ; symbol stub for: __kmpc_for_static_fini
0x100000b83 <+523>: movl $0x0, %eax
0x100000b88 <+528>: movq -0x28(%rbp), %rbx
0x100000b8c <+532>: movq -0x20(%rbp), %r12
0x100000b90 <+536>: movq -0x18(%rbp), %r13
0x100000b94 <+540>: movq -0x10(%rbp), %r14
0x100000b98 <+544>: movq -0x8(%rbp), %r15
0x100000b9c <+548>: leave
0x100000b9d <+549>: retq
0x100000b9e <+550>: pushq %rbp
0x100000b9f <+551>: movq %rsp, %rbp
0x100000ba2 <+554>: subq $0xc0, %rsp
0x100000ba9 <+561>: movq %r15, -0x8(%rbp)
0x100000bad <+565>: movq %r14, -0x10(%rbp)
0x100000bb1 <+569>: movq %r13, -0x18(%rbp)
0x100000bb5 <+573>: movq %r12, -0x20(%rbp)
0x100000bb9 <+577>: movq %rbx, -0x28(%rbp)
0x100000bbd <+581>: movq %rdi, -0x48(%rbp)
0x100000bc1 <+585>: movq %rsi, -0x40(%rbp)
0x100000bc5 <+589>: movq -0x48(%rbp), %rax
0x100000bc9 <+593>: movl (%rax), %eax
0x100000bcb <+595>: movl %eax, -0x74(%rbp)
0x100000bce <+598>: movl $0x1, -0xb8(%rbp)
0x100000bd8 <+608>: movl $0x2, -0xb4(%rbp)
0x100000be2 <+618>: movl -0xb8(%rbp), %eax
0x100000be8 <+624>: movl -0xb4(%rbp), %edx
0x100000bee <+630>: cmpl %edx, %eax
0x100000bf0 <+632>: jl 0x100000a8e ; <+278> at foo.c:5
0x100000bf6 <+638>: jmp 0x100000b83 ; <+523> at foo.c:5
0x100000bf8 <+640>: movl -0x78(%rbp), %eax
0x100000bfb <+643>: movl -0x7c(%rbp), %edx
0x100000bfe <+646>: movl %edx, -0xb8(%rbp)
0x100000c04 <+652>: movl -0xb8(%rbp), %edx
0x100000c0a <+658>: cmpl %eax, %edx
0x100000c0c <+660>: jg 0x100000b6f ; <+503> at foo.c:5
0x100000c12 <+666>: leaq 0x4e7(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000c19 <+673>: movq %rax, %rdi
0x100000c1c <+676>: movl $0x0, %eax
0x100000c21 <+681>: callq 0x100000ece ; symbol stub for: __kmpc_ok_to_fork
0x100000c26 <+686>: movl %eax, -0x70(%rbp)
0x100000c29 <+689>: movl -0x70(%rbp), %eax
0x100000c2c <+692>: testl %eax, %eax
0x100000c2e <+694>: jne 0x100000c84 ; <+780> at foo.c:7
0x100000c30 <+696>: leaq 0x4c9(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000c37 <+703>: movq %rax, %rdi
0x100000c3a <+706>: movl -0x74(%rbp), %eax
0x100000c3d <+709>: movl %eax, %esi
0x100000c3f <+711>: movl $0x0, %eax
0x100000c44 <+716>: callq 0x100000ed4 ; symbol stub for: __kmpc_serialized_parallel
0x100000c49 <+721>: movq -0x48(%rbp), %rax
0x100000c4d <+725>: leaq 0x4f8(%rip), %rdx ; __kmpv_zero_main_1
0x100000c54 <+732>: leaq -0xb8(%rbp), %rcx
0x100000c5b <+739>: movq %rax, %rdi
0x100000c5e <+742>: movq %rdx, %rsi
0x100000c61 <+745>: movq %rcx, %rdx
0x100000c64 <+748>: callq 0x100000dea ; <+1138> at foo.c:7
0x100000c69 <+753>: leaq 0x490(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000c70 <+760>: movq %rax, %rdi
0x100000c73 <+763>: movl -0x74(%rbp), %eax
0x100000c76 <+766>: movl %eax, %esi
0x100000c78 <+768>: movl $0x0, %eax
0x100000c7d <+773>: callq 0x100000eb0 ; symbol stub for: __kmpc_end_serialized_parallel
0x100000c82 <+778>: jmp 0x100000cb3 ; <+827> at foo.c:7
0x100000c84 <+780>: leaq 0x475(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000c8b <+787>: movl $0x1, %edx
0x100000c90 <+792>: leaq 0x153(%rip), %rcx ; <+1138> at foo.c:7
0x100000c97 <+799>: leaq -0xb8(%rbp), %rbx
0x100000c9e <+806>: movq %rax, %rdi
0x100000ca1 <+809>: movl %edx, %esi
0x100000ca3 <+811>: movq %rcx, %rdx
0x100000ca6 <+814>: movq %rbx, %rcx
0x100000ca9 <+817>: movl $0x0, %eax
0x100000cae <+822>: callq 0x100000ec2 ; symbol stub for: __kmpc_fork_call
0x100000cb3 <+827>: movl -0x78(%rbp), %eax
0x100000cb6 <+830>: movl $0x1, %edx
0x100000cbb <+835>: addl -0xb8(%rbp), %edx
0x100000cc1 <+841>: movl %edx, -0xb8(%rbp)
0x100000cc7 <+847>: movl -0xb8(%rbp), %edx
0x100000ccd <+853>: cmpl %eax, %edx
0x100000ccf <+855>: jle 0x100000c12 ; <+666> at foo.c:7
0x100000cd5 <+861>: jmp 0x100000b6f ; <+503> at foo.c:5
0x100000cda <+866>: movl $0x0, -0xb0(%rbp)
0x100000ce4 <+876>: movl -0xbc(%rbp), %eax
0x100000cea <+882>: movl $0x1, %edx
0x100000cef <+887>: subl %edx, %eax
0x100000cf1 <+889>: movl %eax, -0xac(%rbp)
0x100000cf7 <+895>: movl -0xbc(%rbp), %eax
0x100000cfd <+901>: movl $0x1, %edx
0x100000d02 <+906>: subl %edx, %eax
0x100000d04 <+908>: movl %eax, -0xa8(%rbp)
0x100000d0a <+914>: movl $0x0, -0xa4(%rbp)
0x100000d14 <+924>: movl $0x1, -0xa0(%rbp)
0x100000d1e <+934>: addq $-0x20, %rsp
0x100000d22 <+938>: leaq 0x3d7(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000d29 <+945>: movl $0x22, %edx
0x100000d2e <+950>: leaq -0xa4(%rbp), %rcx
0x100000d35 <+957>: leaq -0xb0(%rbp), %rbx
0x100000d3c <+964>: leaq -0xac(%rbp), %rsi
0x100000d43 <+971>: leaq -0xa0(%rbp), %rdi
0x100000d4a <+978>: movq %rdi, (%rsp)
0x100000d4e <+982>: movl $0x1, 0x8(%rsp)
0x100000d56 <+990>: movl $0x1, 0x10(%rsp)
0x100000d5e <+998>: movq %rax, %rdi
0x100000d61 <+1001>: movl -0x64(%rbp), %eax
0x100000d64 <+1004>: movq %rsi, -0x30(%rbp)
0x100000d68 <+1008>: movl %eax, %esi
0x100000d6a <+1010>: movq %rbx, %r8
0x100000d6d <+1013>: movq -0x30(%rbp), %rax
0x100000d71 <+1017>: movq %rax, %r9
0x100000d74 <+1020>: callq 0x100000ebc ; symbol stub for: __kmpc_for_static_init_4
0x100000d79 <+1025>: addq $0x20, %rsp
0x100000d7d <+1029>: movl -0xb0(%rbp), %eax
0x100000d83 <+1035>: movl %eax, -0x6c(%rbp)
0x100000d86 <+1038>: movl -0xac(%rbp), %edx
0x100000d8c <+1044>: movl %edx, -0x68(%rbp)
0x100000d8f <+1047>: movl %edx, -0x68(%rbp)
0x100000d92 <+1050>: movl -0xa8(%rbp), %edx
0x100000d98 <+1056>: cmpl %edx, %eax
0x100000d9a <+1058>: jg 0x100000dbb ; <+1091> at foo.c:7
0x100000d9c <+1060>: movl -0xa8(%rbp), %eax
0x100000da2 <+1066>: movl -0x68(%rbp), %edx
0x100000da5 <+1069>: cmpl %eax, %edx
0x100000da7 <+1071>: jle 0x100000e48 ; <+1232> at foo.c:7
0x100000dad <+1077>: movl -0xa8(%rbp), %eax
0x100000db3 <+1083>: movl %eax, -0x68(%rbp)
0x100000db6 <+1086>: jmp 0x100000e48 ; <+1232> at foo.c:7
0x100000dbb <+1091>: leaq 0x33e(%rip), %rax ; .2.1_2_kmpc_loc_struct_pack.28
0x100000dc2 <+1098>: movq %rax, %rdi
0x100000dc5 <+1101>: movl -0x64(%rbp), %eax
0x100000dc8 <+1104>: movl %eax, %esi
0x100000dca <+1106>: callq 0x100000eb6 ; symbol stub for: __kmpc_for_static_fini
0x100000dcf <+1111>: movl $0x0, %eax
0x100000dd4 <+1116>: movq -0x28(%rbp), %rbx
0x100000dd8 <+1120>: movq -0x20(%rbp), %r12
0x100000ddc <+1124>: movq -0x18(%rbp), %r13
0x100000de0 <+1128>: movq -0x10(%rbp), %r14
0x100000de4 <+1132>: movq -0x8(%rbp), %r15
0x100000de8 <+1136>: leave
0x100000de9 <+1137>: retq
0x100000dea <+1138>: pushq %rbp
0x100000deb <+1139>: movq %rsp, %rbp
0x100000dee <+1142>: subq $0xc0, %rsp
0x100000df5 <+1149>: movq %r15, -0x8(%rbp)
0x100000df9 <+1153>: movq %r14, -0x10(%rbp)
0x100000dfd <+1157>: movq %r13, -0x18(%rbp)
0x100000e01 <+1161>: movq %r12, -0x20(%rbp)
0x100000e05 <+1165>: movq %rbx, -0x28(%rbp)
0x100000e09 <+1169>: movq %rdi, -0x60(%rbp)
0x100000e0d <+1173>: movq %rsi, -0x58(%rbp)
0x100000e11 <+1177>: movq %rdx, -0x50(%rbp)
0x100000e15 <+1181>: movq -0x60(%rbp), %rax
0x100000e19 <+1185>: movl (%rax), %eax
0x100000e1b <+1187>: movl %eax, -0x64(%rbp)
0x100000e1e <+1190>: movl $0x0, -0xc0(%rbp)
0x100000e28 <+1200>: movl $0x1, -0xbc(%rbp)
0x100000e32 <+1210>: movl -0xc0(%rbp), %eax
0x100000e38 <+1216>: movl -0xbc(%rbp), %edx
0x100000e3e <+1222>: cmpl %edx, %eax
0x100000e40 <+1224>: jl 0x100000cda ; <+866> at foo.c:7
0x100000e46 <+1230>: jmp 0x100000dcf ; <+1111> at foo.c:7
0x100000e48 <+1232>: movl -0x68(%rbp), %eax
0x100000e4b <+1235>: movl -0x6c(%rbp), %edx
0x100000e4e <+1238>: movl %edx, -0xc0(%rbp)
0x100000e54 <+1244>: movl -0xc0(%rbp), %edx
0x100000e5a <+1250>: cmpl %eax, %edx
0x100000e5c <+1252>: jle 0x100000e85 ; <+1293> at foo.c:9
0x100000e5e <+1254>: jmp 0x100000dbb ; <+1091> at foo.c:7
0x100000e63 <+1259>: movl -0x68(%rbp), %eax
0x100000e66 <+1262>: movl $0x1, %edx
0x100000e6b <+1267>: addl -0xc0(%rbp), %edx
0x100000e71 <+1273>: movl %edx, -0xc0(%rbp)
0x100000e77 <+1279>: movl -0xc0(%rbp), %edx
0x100000e7d <+1285>: cmpl %eax, %edx
0x100000e7f <+1287>: jg 0x100000dbb ; <+1091> at foo.c:7
-> 0x100000e85 <+1293>: leaq 0xc8(%rip), %rax
0x100000e8c <+1300>: movl -0x84(%rbp), %edx
0x100000e92 <+1306>: movq %rax, %rdi
0x100000e95 <+1309>: movl %edx, %esi
0x100000e97 <+1311>: movl $0x0, %eax
0x100000e9c <+1316>: callq 0x100000eda ; symbol stub for: printf
0x100000ea1 <+1321>: jmp 0x100000e63 ; <+1259> at foo.c:8
0x100000ea3 <+1323>: nop
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Yes, the code is legal. Thanks for creating a small reproducer - I will try on Mac system as well (no issue on Windows and Linux).
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Could you please let me know the number of threads you set while running this example? I still not able to reproduce it on Mac OS as well.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
The number of threads is 4, as my environment has 4 logical cores. But even when OMP_NUM_THREADS is set to another value, I get the same result.
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Let me make a correction. The compilation command was actually `icc -qopenmp -std=c11 foo.c` (I forgot that `icc` is an alias for `icc -std=c11 in my environment). The compilation fails without specifying c99 or above.
The problem seems to occur only when i is declared in initialization part of the for statement. So if you modified the reproducer like this, this is why you couldn't reproduce it.
Sorry for incomplete information.
#include <stdio.h>
int main(void)
{
int i;
#pragma omp parallel for
for (i = 1; i < 2; i++) {
int j;
#pragma omp parallel for
for (j = 0; j < 1; j++) {
printf("%d\n", i);
}
}
}
- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Report Inappropriate Content
Thanks. Now I can reproduce the problem. It doesn't fail if icpc is used, so, something with c99. I escalated this to developers (DPD200416367);
Reply
Topic Options
- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Printer Friendly Page