experiment to add -ftrampoline-impl=heap for gfortran

See #599

Author: jacobwilliams

CMakeLists.txt

@@ -235,6 +235,12 @@ set_target_properties ( ${LIB_NAME}
   LIBRARY_OUTPUT_DIRECTORY ${PROJECT_BINARY_DIR}/lib
   Fortran_MODULE_DIRECTORY ${PROJECT_BINARY_DIR} )
 
+# Add trampoline heap implementation flag for gfortran on Linux
+if(CMAKE_Fortran_COMPILER_ID STREQUAL "GNU" AND CMAKE_SYSTEM_NAME STREQUAL "Linux")
+  target_link_options(${LIB_NAME} PRIVATE -ftrampoline-impl=heap)
+  target_link_options(${LIB_NAME}-static PRIVATE -ftrampoline-impl=heap)
+endif()
+
 #-------------------------------------
 # Build the documentation with FORD
 #-------------------------------------

fpm.toml

@@ -7,6 +7,10 @@ homepage = "https://github.com/jacobwilliams/json-fortran"
 categories = ["io"]
 keywords = ["JSON"]
 
+[features]
+debug.gfortran.linux.link-time-flags = "-ftrampoline-impl=heap"
+release.gfortran.linux.link-time-flags = "-ftrampoline-impl=heap"
+
 [build]
 external-modules = "ifcore"
 auto-executables = true

json-fortran.fobis

@@ -12,6 +12,7 @@ $FORD_FILE    = ford.md
 $STATIC_LIB   = libjsonfortran.a
 $SHARED_LIB   = libjsonfortran.so
 $OPTIMIZE     = -O2
+$LFLAGS_GNU   = -ftrampoline-impl=heap
 $CSTATIC_GNU  = -c -fbacktrace -Wall -Wextra -Wno-maybe-uninitialized -Wno-unused-function -pedantic
 $DEBUG_GNU    = -O0 -g3 -Warray-bounds -Wcharacter-truncation -Wline-truncation -Wimplicit-interface -Wimplicit-procedure -Wunderflow -fcheck=all -fmodule-private -ffree-line-length-132 -fimplicit-none -fbacktrace -fdump-core -finit-real=nan -fall-intrinsics
 $CSTATIC_INT  = -c -std18
@@ -69,12 +70,14 @@ exclude_dirs    = $EXCLUDE_DIRS
 description     = Build library with GNU gfortran by optimized-static flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $OPTIMIZE
+lflags          = $LFLAGS_GNU
 template        = template-static
 
 [static-gnu-debug]
 description     = Build library with GNU gfortran by debug-static flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $DEBUG_GNU
+lflags          = $LFLAGS_GNU
 template        = template-static
 
 [static-intel]
@@ -93,12 +96,14 @@ template        = template-static
 description     = Build library with GNU gfortran by optimized-shared flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $OPTIMIZE
+lflags          = $LFLAGS_GNU
 template        = template-shared
 
 [shared-gnu-debug]
 description     = Build library with GNU gfortran by debug-shared flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $DEBUG_GNU
+lflags          = $LFLAGS_GNU
 template        = template-shared
 
 [shared-intel]
@@ -118,12 +123,14 @@ template        = template-shared
 description     = Build all tests with GNU gfortran by optimized-static flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $OPTIMIZE
+lflags          = $LFLAGS_GNU
 template        = template-tests
 
 [tests-gnu-debug]
 description     = Build all tests with GNU gfortran by debug-static flags
 compiler        = gnu
 cflags          = $CSTATIC_GNU $DEBUG_GNU
+lflags          = $LFLAGS_GNU
 template        = template-tests
 
 [tests-intel]